Walaykum asalam warahmatullahi wabarakatahu
If she is new to islam then, whatever traits personality character she has will still be there BUT will slowly change to adhere to islamic principles as her emaan grows and she has better understanding & grasp of what being a muslim entails, as "mi hermana" @umm[emoji173]layth said [emoji6] IT WILL TAKE TIME, IT DOES NOT HAPPEN IMMEDIATELY, it takes everything out of you to completely do a 180° spin on your life and change everything you knew and grew up doing as it was basically "haram" or not in line with being a muslim, its NOT EASY at all and we all struggle with something nobody is perfect at all.
We all know backbiting & slandering is NOT part of islam & against Quran/Sunnah, has very dire consequences if you don't repent for it, but yet its a very big problem among muslims, how can you expect a brand new muslim to basically be perfect when people who were born & grew up as muslims have these characteristics & traits some even worse, your basically throwing her under a bus when shes still learning probally finding it hard to adapt to all the changes,
Among latina/hispanic/spanish (whatever lol) it is common that they "talk alot" i.e problems with family etc get spoken about as a normalcy so if she grew up with that its probally very normal to her & comes as a second nature without really realising whats shes doing, again as she learns islam her emaan grows it will cut down and ultimately stop in sha Allah.
So to help stop this, i think you should back off abit as again she may be finding all these changes stressfull to deal with adding on with the constant arguements (whatever its about) sounds like added stress, she may not have anyone to speak to as she may feel that you are too judgey & forcefull with these changes (she may feel you expect her to change overnight and when its not done you hold judgement against her) instead of realising that for a revert this is an entirely new life and it has to be taken slow in order for the changes to stick and not go back on oneself.
So try explaining to her that how would she like it if you do what shes doing to you i.e the situation was reversed, use a logical approach try not to shout or loose your temper, this is the best time for you to show the example of what being a muslim is about, YOU NEED TO BE HER EXAMPLE so not loosing your temper being calm as YOUR the husband and she is learning her islam from YOU would be a great start.
You could also encourage her if she hasnt to find any sisters who have a similar background as her who could be helpfull as they understand the culture and everything that she has to leave behind, its more comforting to find people who understand where your coming from to help you keep going with motivation and help.
Plus if she is doing other good things then praise her, like tell her she is doing a good job, make her feel proud of herself on other things she is doing don't just get hung up on one thing as then its like your ignoring everything good about her and just focusing on the bad, it may put her off and push her to speak to people.
You could also say to her while she works on that you will work on something yourself while helping eachother i.e your temper
Sulayman ibn Sard said: "I was sitting with the Prophet (peace and blessings of Allaah be upon him), and two men were slandering one another. One of them was red in the face, and the veins on his neck were standing out. The Prophet (peace and blessings of Allaah be upon him) said, ‘I know a word which, if he were to say it, what he feels would go away. If he said "I seek refuge with Allaah from the Shaytaan," what he feels (i.e., his anger) would go away.’" (Reported by al-Bukhaari, al-Fath, 6/337)
The Prophet (peace and blessings of Allaah be upon him) said: "If a man gets angry and says, ‘I seek refuge with Allaah,’ his anger will go away." (Saheeh al-Jaami’ al-Sagheer, no. 695)
The Messenger of Allaah (peace and blessings of Allaah be upon him) said: "If any of you becomes angry, let him keep silent." (Reported by Imaam Ahmad, al-Musnad, 1/329; see also Saheeh al-Jaami’, 693, 4027).
The Messenger of Allaah (peace and blessings of Allaah be upon him) said: "If any of you becomes angry and he is standing, let him sit down, so his anger will go away; if it does not go away, let him lie down."
The narrator of this hadeeth (report) is Abu Dharr (may Allaah be pleased with him), and there is a story connected to his telling of it: he was taking his camels to drink at a trough that he owned, when some other people came along and said (to one another), "Who can compete with Abu Dharr (in bringing animals to drink) and make his hair stand on end?" A man said, "I can," so he brought his animals and competed with Abu Dharr, with the result that the trough was broken. [i.e., Abu Dharr was expecting help in watering his camels, but instead the man misbehaved and caused the trough to be broken]. Abu Dharr was standing, so he sat down, then he laid down. Someone asked him, "O Abu Dharr, why did you sit down then lie down?" He said: "The Messenger of Allaah (peace and blessings of Allaah be upon him) said: . . ." and quoted the hadeeth. (The hadeeth and this story may be found in Musnad Ahmad, 5/152; see also Saheeh al-Jaami’, no. 694).
Abu Hurayrah, may Allaah be pleased with him, reported that a man said to the Prophet (peace and blessings of Allaah be upon him), "Advise me." He said, "Do not become angry." The man repeated his request several times, and each time the Prophet (peace and blessings of Allaah be upon him) told him, "Do not become angry." (Reported by al-Bukhaari, Fath al-Bari, 10/456)
According to another report, the man said: "I thought about what the Prophet (peace and blessings of Allaah be upon him) said, and I realized that anger combines all kinds of evil." (Musnad Ahmad, 5/373)
(5)Do not become angry and Paradise will be yours (a saheeh (authentic) hadeeth, see Saheeh al-Jaami’, 7374. Ibn Hijr attributed it to al-Tabaraani, see al-Fath 4/465):
In sha Allah things get better for you both and your marriage gets back on track
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